Idaho air quality is in the red. So where’s the wildfire smoke coming from this time?

Smoke envelopes the foothills behind downtown Boise as photographed from the Boise Depot on Monday afternoon.
Smoke envelopes the foothills behind downtown Boise as photographed from the Boise Depot on Monday afternoon.

Boise skies became even more gray on Tuesday after nearby wildfires left a thick layer of smoky air across the Pacific Northwest, pushing Treasure Valley air quality into a red alert.

The Air Quality Index on Tuesday was “unhealthy,” and vulnerable people were urged to avoid heavy exertion. The state Department of Environmental Quality issued a statewide air quality advisory Tuesday morning that extends through 10 a.m. Thursday, Sept. 7.

Boise and West Ada school districts canceled outdoor after-school activities and kept students indoors during recess.

Across the state, air quality ranged from Moderate to Very Unhealthy. The advisory puts into effect a statewide burn ban for all types of fires.

The National Weather Service reported that smoke layers are spreading not only from local fires and those the Cascades, but also fires in British Columbia and Montana.

This forecast from the National Weather Service shows wildfire smoke stretching across the country for the next few days.

Montana and British Columbia have been particularly hard-hit. Montana had 26 active wildfires as of Monday, according to the National Interagency Fire Center, based in Boise. Flames have forced evacuations, trapped firefighters and burned a Glacier National Park lodge, writes the Missoulian. On Friday, Montana Gov. Steve Bullock issued a disaster declaration. (Here’s a map of fire locations.)

British Columbia is having its worst fire season on record, according to news agencies there. Here’s a rundown of its fires.

Locally, NIFC listed six major wildfires in Idaho on Monday, including one, the Bearskin Fire, 21 miles north of Lowman. Just Friday, Boise air quality took a dive when firefighters had to battle a 200-acre wildfire in the Foothills near Pierce Park. Two juveniles accidentally started the fire in their backyard.

The Idaho Department of Environmental Quality issued a yellow, or moderate air quality alert on Monday for the Treasure Valley, citing both local and regional wildfire activity. During a yellow air quality alert, the air quality can impact the health of sensitive populations such as children, the elderly, or people with lung and heart conditions. The air quality alert will stay moderate on Tuesday, according to the DEQ.

Outdoor burning bans are also in place in Ada and Canyon counties.

Multiple recent wildfires created smoky skies in the Pacific Northwest on Labor Day.